Horse riding exerciser



FIG. 1 is a front view thereof;

FIG. 2 is a front perspective view thereof;

FIG. 3 is a top view thereof;

FIG. 4 is a left view thereof;

FIG. 5 is a right view thereof;

FIG. 6 is a back view thereof;

FIG. 7 is a back perspective view thereof; and,

FIG. 8 is a bottom view thereof. 

The ornamental design for a horse riding exerciser, as shown and described. 